The ex-flight attendant was back in Mental Health Court for graduation from the mandated mental-rehab program, walking away with a year’s probation and a $10,000 bill from the airline.

“I’m very optimistic,” he said. “A lot of the people I came across didn’t have the resources and weren’t so fortunate.”

Slater gained notoriety across the nation when he grabbed some beers, deployed his JetBlue plane’s emergency chute on the JFK tarmac and slid right off his job after an argument with a testy passenger.

‘I’ve had it! To the passenger who called me a motherf—-r, f–k you! . . . I’m done!” he bellowed into the plane intercom before taking the slide.

An hour later, cops arrested him at the Rockaway Park, Queens, home he shared with his boyfriend.

The over-the-top drama nearly landed Slater in jail for seven years — the maximum he faced on felony charges of reckless endangerment and criminal mischief, as well as criminal trespass.

Instead, in October 2010, Slater pleaded guilty to attempted criminal mischief, went into counseling and rehab and got hit with a $10,000 restitution bill from JetBlue. At yesterday’s hearing, a payment schedule of $831.25 a month was put into place.

He declared he wouldn’t board another JetBlue flight “until hell freezes over” — but gets lots of support on other carriers.

“When I fly, it’s actually a lot of fun,” he said. “It’s very celebratory. There’s a lot of high-fives. I’m usually in the galley with the crews. I still end up picking up trash. I end up serving passengers.”

Dressed in a dark suit, sporting close-cropped hair, Slater told Judge Marcia Hirsch the court’s mental- health program made “a difficult time in my life as manageable as possible.”

“Mr. Slater, are you ready to leave us?” the judge asked, to which Slater replied, “Yes,” and then laughed.

She then left the bench to hand him a diploma as the courtroom applauded.

Slater said he’s now writing a book chronicling his years in the aviation industry. And he said he’s certain his notorious exit tapped into the frustration of a lot of Americans.

“We all understand what it’s like to be outsourced, underpaid and overworked,” he said.

“I was one person who had a bad day and acted perhaps inappropriately, but in a way that was resonant with many people. And it did give me a voice.”